Mechanical vocal-tract models for speech dynamics

Arai has developed several physical models of the human vocal tract for education and has reported that they are intuitive and helpful for students of acoustics and speech science. We first reviewed dynamic models, including the sliding three-tube (S3T) model and the flexible-tongue model. We then developed a head-shaped model with a sliding tongue, which has the advantages of both the S3T and flexible-tongue models. We also developed a computer-controlled version of the Umeda & Teranishi model, as the original model was hard to manipulate precisely by hand. These models are useful when teaching the dynamic aspects of speech.